The viscoelasticity of biofluids, such as blood clots or mucus, is critical to their performance. Measurement of viscoelastic properties of these fluids can provide valuable information to medical professionals to aid in the diagnosis and treatment of patients. For example, the speed and strength at which a blood clot forms may be affected by genetics, illness, medication, or environment. Analyzing the physical properties of a blood clot may provide important information that is useful in determining how well a treatment is working or is likely to work, or perhaps that a treatment intervention is necessary.
Currently, clot elasticity is measured either at the point of care (POC), usually accompanying surgery, or within an analytical lab setting. Techniques for understanding clot viscoelasticity in a point of care system use several different strategies. One technology employs flow through a tube that is monitored in some way, such as by an optical detection. Another technology uses magnetic beads that become suspended in the developing clot, and the beads are caused to move through the application of a magnetic field. The detection of the moving beads is performed by optics, and the cessation of the bead movement is an indication that the clot has formed.
In an analytical lab setting, techniques such as thromboelastography (TEG) can test the efficiency of coagulation in the blood. TEG uses a macroscopic quantity of specimen and measures the viscoelasticity by moving two surfaces with respect to each other in shear. The geometry is usually that of concentric cylinders. Similar techniques are used for measuring the viscoelasticity of other biofluids such as mucus.
There are disadvantages associated with the current methods of testing rheological properties of biofluids. Laboratory techniques such as TEG are not implemented as high-throughput instruments, so tests must be performed essentially one at a time. Point of care technologies are not as sensitive or quantitative as laboratory tests and so cannot replace laboratory analysis. In addition, macroscopic quantities of specimens are generally needed for laboratory analysis.
Accordingly, in light of these disadvantages associated with biofluid rheology techniques, there exists a need for methods and systems for using surface-attached actuated microposts for assessing biofluid rheology.